Subcooling condenser



A ril 26 1927.

p J. @momia SUBCOOLING CNDENSER Filed May 5. 1921 Snug/Milo@ f 56am/Lug J Patented Api'. 26, 192,7.

UNITED STATES PATENT OFFICE.

ROBERT JEWETT PABODIE, OF MAYWOOD, ILLINOIS, ASSIGNOR TO THE GRISGOM RUSSELL COMPANY, OF NEW YORK, N. `Y., A CORPORATION F DELAWARE.

SUBCOOLING CONDENSER. t

Application filed May 5, 1921. Serial No. 467,010.

The present invention relates to a combined condenser and cooler. The apparatus is adapted to all work in which it is desired to condense vapor and cool the con- A densate, but is particularly designed for use in connection with oil refining.

Combined condensers and coolers have been built in which the medium to be condensed and cooled is contained in tubes sur- 0 rounded by the cooling medium. These tubes extend longitudinally the entire length ot the apparatus,` the vapor entering at one end, being condensed during its passage through the tubes, and the condensate issu- 5 ing trom the other end. The cooling medium is circulated about the tubes in any desired manner. In this type of apparatus the cross section of the tubular passage is constant throughout its entire length. Since the vapor entering the apparatus occupies a much greater volume than a corresponding' weight of condensate. the velocity of How in the upperpart ot' thegtubes, that is, -in the portion where condensation is taking place, is much higher than the velocity of the condensate at the outlet. This high velocity in the tirstfportion ot' the length of the tubes gives rise to an appreciable friction head, and consequently a considerable pressure difference between the inlet and outlet of the tubes Will be required to maintain a steady flow. lt. however, the

tubular cross section is increased to such a value as will obviate this undesirable back pressure, such a large amount of tubing is required as to make the cost of the apparatus prohibitively high.

The present invention has for its principal object to provide a combined condenser and sub-cooling apparatus of the above type in which no appreciable back pressure above outlet pressure is generated when the apparatus is in operation.

llt is also an object of the invention to provide an apparatus of the above type in which the velocity ot flow througout the tubes may be maintained at any" desired value and will be substantially uniform throughout the entire passage. only a small pressure difference being required to maintain this flow.

lt is a further object ot the invention to provide means in an apparatus of this type tor reducing the inlet velocity of the vapor below that ordinarily occurring in such apparatus, and increasing the outlet velocity of the condensate above that usually found.

It is a further object ofthe invention to provide an apparatus of this type which may be built in any capacity or any length, and at the same time utilize lengths of tubing throughout which are well Within the ability of tube mills to produce.

A still further'object is to provide an apparatus of the above type of -moderafte cost and small dimensions which provides a long path for the cooling medium and a long heat transferring period, during which time the entire volume of the cooling medium is broughtrepeatedly in Contact with the tubes. f

In accordance with the above objects, l provide an apparatus comprising a tubular passage whose cross sect-ion varies along the length of the apparatus, this feature being secured by employing a series of sections, each section a complete unit in itself, and thel various sections containing did'erent numbers of tubes. The tubes of the various sections are connected in series and equalizing chambers or compartments are disposed as -desired at the joints between sections.A

By this arrangement a uniform dow from each chamber to the succeeding group of tubing is provided, even though the individual tubes in the preceding group may have discharged unequal amounts into the equalizing chamber due to the inequalities of condensation in the various tubes or other cause.

l have illustrated and described a preterred embodiment ot' my invention in the accompanying drawings and specilication, it being understood that the details of construction, such as the number of sections in the various units, the methods of connecting the sections, and the like, may be varied.

In the said drawings, Fig. l is a longitudinal section of a cooling condenser in accordance with my invention comprising two individual sections; Fig. 2 is a similar view of an apparatus consisting ot three sections; Fig. 3 is a similar view of an apparatus ot the above type in accordance with my invention showing a modification in the means ot connecting two sections.

Referring to the drawings, particularly to Fig. 1, 1 indicates the shell of the upper section, shown here as a cylindrical casting with open ends which are flanged 'or the purpose of attachment -to the other parts ot .ier

the apparatus. An o ning 4 is provided in the wall of the she to serve as an outlet for they cooling liquid. 2 indicates the shell -of the lower section, very similar to the be condensed and cooledand a baille 7 which forms a tortuous passage 7 for the cooling liquid. Tubes 6 are preferably strai ht and of thin metal, supported at the ends y tube plates 8, there being fewer tubes in the lower than in the upper shell. A large supporting tube or cylinder 9 serves to hold the tube plates 8 spaced atthe proper interval and furnishes a rigid support for the unit. The baiiies 7 are provided with 4holes through which the tubes pass and are preferably suported by means' of the tubes and the memer 9. The heating element within each shell is constructed as a unit, and the opening at the upper end of each shell is made suiiiciently large to permit of bodily withdrawal of the element.

The upper end of the apparatus is provided with a head 1() having an inlet 11 and constituting a chamber for the vapor as it is delivered to the apparatus. This upper head 10, together with the up r tube plate 8, of the top section, is secure rigidly to the shell 1. The tubes extend downwardly and terminate in the lower tube late of the upper section which constitutes t ie top of an equalizin chamber 12, the upper tube plate of the 1lower section formin its bottom. The side walls 13 of the equa izing chamber are preferably cast integral with one of the tube plates. The tubes of the last section open into the outlet chamber 14, which in turn communicates with the exterior of the apparatus through an outlet 15. The side walls 16 of the outlet chamber fit snugly against the interior ofthe lower end of the shell 2, thus constituting a sliding fit to allow for expansion and contraction of the tubes. Packing is provided at 17 between the walls of the chamber and the shell to prevent the escape of the circulating liquid from the shell.

The space within the shell surrounding the tubes is preferably provided Vwith a helical baie 7 of the type disclosed in the Patent No. 1,335,506, to R. C. Jones, the baille being of a low pitch to constitute a long tortuous path for the cooling liquid and bring it into intimate contact with the tubes 6. 'Ihe cooling liquid is retained by the side walls of the shell, and a packed joint is provided between the sections 1 and 2 to prevent escape of the liquid. Space is provided between the equalizing chamber 12 and the walls of the shell, the chamber 12 being held and guided for vertical movement due to expansion and contraction of the tubes by supporting members 18 extending between the shell walls and the walls of the chamber.

The vapor as it comes from the evaporators or retorts is lirst admitted to the vapor inlet 1l and enters the tubes 6 of the upper shell, the number of tubes in the upper section being greater than the number in the lower section. 'Ihe cooling liquid is preferably circulated in a direction opposite to that" of the vapor flow and is accordingly admitted to the lower. shell through the inlet 5, from whence it is forced in a tortuous path up through the helical passage 7 into the lower shell, through the space at the outside of the equalizing chamber 12, up through the baille in the upper shell, and thence out through the opening 4. The vapor is largely condensed in the tubes of the upper section and the condensate, together with the vapor still uncondensed, passes into the equalizmg chamber l2, from whence it is fed into the tubes of the lower shell. In passing through these tubes the condensate cornes into heattransferring proximity with the cooling medium shortly after it enters the shell, and the condensate is thereby sub-cooled to any predetermined degree, being then discharged into outlet chamber 14 and from thence through outlet 15 to a storage tank or other suitab e container.

When the vapor is being condensed in the tubes its volume is reduced greatly, and for that reason the tubular cross section of the lowerV unit is much less than that of the upper unit for the purpose of maintaining auniform flow. lVhere tubes extending the entire length of the apparatus are used, this reduction of volume in the lower portions of the tubino would create a' region of lower pressure and` cause the vapor to be sucked into the upper ends of the tubes at a high rate, thus generating an appreciable skin friction which acts to retard rather than increase the rapidity of condensation. This reduced pressure in the tubes above the condensate also greatly retards the flow of the condensate from the discharge port of the apparatus. In accordance with my invention I employ a Ytubular passage of large section in the upper shell and at the same time utilize short lengths of tubing. In this manner the above mentioned velocity increase may be reduced as desired b properly proportioning the number of tu es in the various sections and'constructing each section of the proper length.

The modification illustrated in Fig. 2 is similar to that of Fig. 1 except for the num` lber of sections, vapor being admitted to the inlet 11 passing through the three compartments in-serles, and the condensate bein discharged at the outlet 15. The cooling liquid 'llt lll

is admitted through the opening` 5 in the lower shell 3 and passes up through the passages of the three shells in series, as has Abeen described, and issues from the condenser through the outlet 4. It will be noted that in this modification-the number of tubes in the second and third units is the same. This will be the case in an apparatus in which condensation takes place largely in the upper shell and the lower shells are devoted almost exclusively to sub-cooling the condensate. If, however, the apparatus is designed to accomplish the condensation of the vapor not only in the upper section but in one or more succeeding sections, the cross section of the tubular passage will be varied proportionally' in those sections where condensation occurs, the number of tubes being the same only in those sections devoted to subcooling t e condensate.

In Fig. 3 a further modified construction is shown differing from the previously described devicein the manner of connection of the various sections. A two-unit apparatus is shown, the construction of each unit being substantially as has been described. In this modification, lower shell is provided with a head '19 having an outlet opening into the passage 21, which, assagetserves as a means of communication etween the equalizing chamber 12 of the 'upper section and the head 19 'i of the. lower section. The material to be cooled and condensed, after passing'tlrough the tubesA of the upper sectlon, is collected in the chamber 12, passed through the passage 21 into the chamber 19, from whence it is delivered into the Ltubes of the lower section and linally discharged into the chamber 14 and conveyed through outlet 15 to a reservoir or other storage receptacle.y The cooling medium enters` the lower shell 2 through the opening 5n passes up through the helical passage with' .from -thence passes through the pipe 22'into the shell 1 of the upper section, from where --it -is forced up through the` passa e in the shell 1 and out at the opening 4. his construction obviates the necessity of `provid-- ing a space between the walls of chamber 12 and the shell, since the cooling water is conveyed from one shell to the other through the'external pipe 22. Accordingly, all the sections areprovided with sliding joints 17, identical with those shown on the lower sections in Figs; land 2. The passage 21 is provided with an expansion joint 23, and

l is',

the pipe 22 is provided with anA expansion. joint 24, to compensate for the expansionv and contraction of the shells and tubes as they are subjected toyaryingv temperatures.

It is evident that a considerable deviahowever the 1n the shell` `2, and

.comprising a plurality of sections, a longi tudinal passage for the vapor and condensate 'extending through said sections, said passage comprising a group ot straight tubes in each of the respective sections, said tubes being attached to the casing at one point only and slidably supported in the casing at one point so as to be free. to expand and contract `under the influence of temperature change'. the cross sectional area of the passage being constant throughout each section but vary-ing in the different sections approximately inversely as the density of the medium being conveyed.

2. In a sub-cooling condenser, a casing comprising afplurality of sections, each inclding a shell, a group of tubes in parallel constituting a passage for the vapor and condensate in each section, the number of tubes being different in the various sections and the several groups being connected in series, and a baille in the space surrounding said tubes constituting a tortuous passage for the cooling fluid. 3. In a sub-cooling condenser, comprising a plurality of sections, a longitudinal passage Qfor the vapor and condensate extending through said sections, the cross sectional area of the passage being constant throughout each section but varying in the different sections and decreasing, in the direction of the flo\v, and a tortuous path for the cooling liquid formed by a balile' surrounding said tubes and serving to bring the cooling liquid into intimate contact with said tubes.

4. Ina sub-cooling condenser, a casing comprising a plurality of sections, a longitudinalpassage for the vapor and condensateA extending through said sections and whose cross sectional areak is constant throughout each section but. varies in the different sections and decreases in the direction of the flow, the upper portion of said passage serving -to condense the vapor and the lower portion serving tosub-cool the condensate, and a tortuous path for the cooling liquid formed by a baille surrounding said tubes and serving to bring the cooling liquid into intimate contact with said tubes, the direction of flow of the cooling medium being opposite to that of the vapor and condensate.

In testimony whereof I affix' my signature.

ROBERT JEWETT PABODIE. 

